make dataset parsing more robust

backend/hostadmin/serializers.py

@@ -5,6 +5,32 @@ from hostadmin.models import Domain
 from toolshed.models import Category, Property, Tag
 
 
+class SlugPathField(serializers.SlugRelatedField):
+    def to_internal_value(self, data):
+        path = data.split('/') if '/' in data else [data]
+        candidates = self.get_queryset().filter(name=path[-1])
+        if len(candidates) == 1:
+            return candidates.first()
+        if len(candidates) == 0:
+            raise serializers.ValidationError(
+                "No {} with name '{}' found".format(self.queryset.model.__name__, path[-1]))
+        if len(candidates) > 1 and len(path) == 1:
+            raise serializers.ValidationError("Multiple {}s with name '{}' found, please specify the parent".format(
+                self.queryset.model.__name__, path[-1]))
+        parent = self.to_internal_value('/'.join(path[:-1]))
+        candidates = self.get_queryset().filter(name=path[-1], parent=parent)
+        if len(candidates) == 1:
+            return candidates.first()
+        if len(candidates) == 0:
+            raise serializers.ValidationError(
+                "No {} with name '{}' found".format(self.queryset.model.__name__, path[-1]))
+
+    def to_representation(self, value):
+        source = getattr(value, self.field_name, None)  # should this use self.source?
+        prefix = self.to_representation(source) + '/' if source else ''
+        return prefix + getattr(value, self.slug_field)
+
+
 class DomainSerializer(serializers.ModelSerializer):
     owner = OwnerSerializer(read_only=True)
 
@@ -12,12 +38,21 @@ class DomainSerializer(serializers.ModelSerializer):
         model = Domain
         fields = ['name', 'owner', 'open_registration']
 
-    def create(self, validated_data):
-        return super().create(validated_data)
-
 
 class CategorySerializer(serializers.ModelSerializer):
-    parent = serializers.SlugRelatedField(slug_field='name', queryset=Category.objects.all(), required=False)
+    parent = SlugPathField(slug_field='name', queryset=Category.objects.all(), required=False)
+
+    def validate(self, attrs):
+        if 'name' in attrs:
+            if '/' in attrs['name']:
+                raise serializers.ValidationError("Category name cannot contain '/'")
+        return attrs
+
+    def create(self, validated_data):
+        try:
+            return Category.objects.create(**validated_data)
+        except Exception as e:
+            raise serializers.ValidationError(e)
 
     class Meta:
         model = Category
@@ -27,7 +62,19 @@ class CategorySerializer(serializers.ModelSerializer):
 
 
 class PropertySerializer(serializers.ModelSerializer):
-    category = serializers.SlugRelatedField(slug_field='name', queryset=Category.objects.all(), required=False)
+    category = SlugPathField(slug_field='name', queryset=Category.objects.all(), required=False)
+
+    def validate(self, attrs):
+        if 'name' in attrs:
+            if '/' in attrs['name']:
+                raise serializers.ValidationError("Property name cannot contain '/'")
+        return attrs
+
+    def create(self, validated_data):
+        try:
+            return Property.objects.create(**validated_data)
+        except Exception as e:
+            raise serializers.ValidationError(e)
 
     class Meta:
         model = Property
@@ -38,7 +85,19 @@ class PropertySerializer(serializers.ModelSerializer):
 
 
 class TagSerializer(serializers.ModelSerializer):
-    category = serializers.SlugRelatedField(slug_field='name', queryset=Category.objects.all(), required=False)
+    category = SlugPathField(slug_field='name', queryset=Category.objects.all(), required=False)
+
+    def validate(self, attrs):
+        if 'name' in attrs:
+            if '/' in attrs['name']:
+                raise serializers.ValidationError("Tag name cannot contain '/'")
+        return attrs
+
+    def create(self, validated_data):
+        try:
+            return Tag.objects.create(**validated_data)
+        except Exception as e:
+            raise serializers.ValidationError(e)
 
     class Meta:
         model = Tag